‘Heartbleed’ computer bug causing global security headaches

SAN FRANCISCO—A confounding computer bug called “Heartbleed” is causing major security headaches across the Internet as websites scramble to fix the problem and Web surfers wonder whether they should change their passwords to prevent theft of their email accounts, credit card numbers and other sensitive information.

The breakdown revealed this week affects a widely-used encryption technology that supposedly protects online accounts for a variety of communications and electronic commerce.

Security researchers who uncovered the threat are particularly worried about the lapse because it went undetected for more than two years. They fear computer hackers may have been secretly exploiting the problem before its discovery.

It’s also possible that no one took advantage of the flaw before its existence was announced late Monday.

Although there is now a way to close the security hole, there are still plenty of reasons to be concerned, said David Chartier, CEO of Codenomicon. A small team from the Finnish security firm diagnosed Heartbleed while working independently from another Google Inc. researcher who also discovered the threat.

“I don’t think anyone that had been using this technology is in a position to definitively say they weren’t compromised,” Chartier said.

Canada’s tax agency isn’t taking any chances. Citing the security risks posed by Heartbleed, the Canada Revenue Agency shut off public access to its website “to safeguard the integrity of the information we hold,” according to a notice posted on its website Wednesday. The agency said it hopes to re-open its website this weekend. The lockdown comes just three weeks from Canada’s April 30 deadline for filing 2013 tax returns.

The U.S. Internal Revenue Service said in a statement Wednesday that it’s not affected by the security hole, advising taxpayers to continue filing their tax returns as they normally would.

TurboTax, the most popular tax preparation software, also issued a Wednesday statement reassuring people that its website is now protected against Heartbleed.

Computer security experts are still advising people to consider changing all their online passwords.

“I would change every password everywhere because it’s possible something was sniffed out,” said Wolfgang Kandek, chief technology officer for Qualys, a maker of security-analysis software. “You don’t know because an attack wouldn’t have left a distinct footprint.”

Google is so confident that it inoculated itself against the Heartbleed bug before any damage could be done that the Mountain View, Calif., company is telling its users they don’t have to change the passwords they use to access Gmail, YouTube and other product accounts. More than 425 million Gmail accounts alone have been set up worldwide.

Facebook, which has more than 1.2 billion accountholders, also believes its online social network has purged the Heartbleed threat. But the Menlo Park, Calif., company encouraged “people to take this opportunity to follow good practices and set up a unique password for your Facebook account that you don’t use on other sites.”

Online short messaging service Twitter Inc. and e-commerce giant Amazon.com Inc. say their websites weren’t exposed to Heartbleed. Ebay Inc., which runs the PayPal payment service as well as online shopping bazaars, says most of its services avoided the bug.

Indeed, very few websites have thus far acknowledged being afflicted by Heartbleed, although the bug is believed to be widespread.

Heartbleed creates an opening in SSL/TLS, an encryption technology marked by the small, closed padlock and “https:” on Web browsers to signify that traffic is secure. The flaw makes it possible to snoop on Internet traffic even if the padlock had been closed. Interlopers could also grab the keys for deciphering encrypted data without the website owners knowing the theft had occurred, according to security researchers.

The problem affects only the variant of SSL/TLS known as OpenSSL, but that happens to be one of the most common on the Internet.

That means the information passing through hundreds of thousands of websites could be vulnerable, despite the protection offered by encryptions. Beside emails and chats, OpenSSL is also used to secure virtual private networks, which are used by employees to connect with corporate networks seeking to shield confidential information from prying eyes.

Heartbleed exposed a weakness in encryption at the same time that major Internet services such as Yahoo, Google, Microsoft and Facebook are expanding their usage of that technology to reassure the users about the sanctity of their personal data.

The additional security measures are being adopted in response to mounting concerns about the U.S. government’s surveillance of online activities and other communications. The snooping has been revealed during the past 10 months through a series of leaked documents from former NSA contractor Edward Snowden.

Anick Jesdanun reported from New York.